This study evaluated the effect of acute toxicity of three commercial inorganic fertilizer NPK 15:15:15, NPK-1; NK 20:20:20, NPK-2; urea and Single superphostate on Clarias gariepinus juveniles on in static condition. The concentration of NPK-1, NPK-2, urea and single superphosphate that killed 50% of the African Catfish with 96-h LC50 were 6.25g/l, 7.25g,/l, 16.25 and 12.50g/l, respectively. For water quality parameters, there was no significant difference (p<0.05) in the mean of (temperature, Ph and alkalinity, while there was significant difference (p<0.05) in Dissolve oxygen. However, urea treatment parameters was were found to have most highest numerical value among the treatments in the water treatment parameters. Furthermore, there was significant difference (p<0.05) in the water treatment parameters. Furthermore, there was significant difference (p<0.05) in the haemoglobin percentage among the treatments while no significant ddifference (p<0.05) was observed on in the total count of red blood cell. Planktons were more abundant in urea treatment but more diverse in Single Superphosphate treatment. All the treatments caused damage on the tissues among which are; nuclear pycnosis in the liver tissue and hyperplasia of mucous cell of skin and gill tissue. However, the most damages were observed on the urea treatments. The study concluded that urea is more toxic to the fish than other inorganic fertilizers.